Elevator construction



May 31,1932. I B, PALM 1,861,063

ELEVATOR CONSTRUCTION Filed Feb. 21, 1929 2 Sheets-Sheet 1 1 i 1 24 i Z4 1 33 i i 33 i attomeqo.

May 31, 1932. PALM 1,861,063

Y ELEVATOR CONSTRUCTION Filed Feb. 21, 1929 v 2 Sheets-Sheet 2 jlakejaZm Guam; :1.

Patented May- 31, 1932 UNITED STATES PATENT orrlcr.

BLAKE PALM, OF WASHINGTON; DISTRICT OF COLUMBIA, ASSIGNOR TO OTIS ELEVATOR COMPANY, NEW YORK, N. Y., A CORPORATION OF NEW JERSEY ELEVATOR CONSTRUCTION Application filed February 21, 1929. Serial No. 341,692.

' This invention relates to a compensating sheave especially designed for use in elevator construction, the primary object of the invention being to provide means to insure against'slack in theelevator cables when the safeties function or X when the elevator or counterweight strike the buffers in the elevator pit, thereby eliminating the possibility of undue strain being directed to the stationary elements of the elevator construction.

Another object of the invention is to provide means for compensating for the expansion and contraction of the elevator cables due to heat and cold to insure a constant tension on the elevator cables under normal proceeds, the invention resides in the combination and arrangement of partsand in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the in- 0 vention herein disclosed, may be made within the scope of what is claimed, without departing from the spirit of the invention.

Referring to the drawings: Figure 7 1 is a vertical sectional view through a sheave and its supporting structure.

Figure 2 is a sectional view taken on line 2-2 of Figure 1. I Figure 3 is a sectional view taken on line 33 of Figure 1.

Figure 4 is a fragmental sectional view, illustrating a modified form of the invention. Figure 5 is a diagram illustrating slack in an elevator cable when the elevator is stopped suddenly;

Referring to the drawings in detail the,

reference character 5 designates a base which is provided wlth an opening 6 defining a passageway therein, the ends of the passageways being open to the upper surface of the base, as at 7.

The reference character 8 designates a cyllnder, there being one of such cylinders positioned over each opening 7 so that liquid may pass through the passageway 6 and enter the cylinders at the lower ends thereof.

Each of these cylinders is provided with a lateral longitudinal passageway 9 open at 1ts lower end as at 10 to establish communication between the passageway and lower end of the cylinder. At the upper end ofeach passageway 9 are valve seats 11, the valve seats being formed in the partitioning member 12 at the upper end of the passageway, there being provided a lug 13 extending from the partitioning member 12 to receive the threaded member 14 that passes through an opening formed in the spring supporting .member 15, to secure the spring supporting member in position.

A nut indicated at 16 is positioned on the threaded member 14 and may be adjusted on the threaded member 14 to hold the member 15 in various positions of adjustment. Recesses are formed in the member 15 and accommodate the outer ends of the coiled springl7, the inner ends of the coiled springs 7 being positioned over the lugs 18 of the valves 19 so that the valves 19 are normally under the action of the coiled springs 18 which seat the valves. By adjusting the nut16, it will be obvious that the tension of the coiled springs 18 may be adjusted to regulate the action of the valve.

These cylinders are supported on opposite Connected with each piston 21 is a piston rod 22, the upper ends of the rods being cured within openings formed at the ends of the cross heads 23, as by means of the nuts 24 that are positioned on the threaded ends 25 of the piston rods. Since the lower end of the sheave housing 20 is normally disposed in spaced relation with the base 5, it will be seen that slight downward movement of the sheave and its housing will be permitted under expansion of the elevator cable that up crates over the sheave. It will be understood that base 5 is secured in the elevator pit, as, for example, by bolts passing through holes 47.

In each piston 21 are valve openings in which the valves 26 operate, the valves 26 being limited in their movements in one direction by means of the guards 27 which are disposed directly over the valve. An open- 28 is formed in each piston, the openings L Fthe pistons being substantially small .so that the liquid in the cylinder may pass from the up )81 side of the piston to the lower side thereo or vice versa upon movement of the sheave under expansion or contraction of the cable operating thereover. I

The sheave is indicated by the reference character 29, and Operates on the shaft 30 sup orted in the sheave housing, the elevator cab e (not shown) passing into the grooves 31 formed in the periphery thereof.

As clearly shown by Figure 1 of the drawings the upper ends of the longitudinal passageways 9 are enlarged to define valve housings which are closed by means of the removable plates 32'. This construction enables ready access to the valves 19 so that they may be readily adjusted or repaired. Removable cylinder heads 38 are provided on the cylinders. These heads are provided with suitable packing means for insuring a fluid tight connection between the piston rods and the cylinder heads 33.

From the foregoing it will be obvious that due to the construction shown and described, the elevator sheave at the bottom of the elevator well. may move slightly vertically under undue strain, movement of the sheave being permitted by the pistons 21 operating in their cylinders to force the liquid contained in the cylinders, through the valves 19 from where the liquid passes to the bottom of the cylinder.

In the form of the invention as illustrated by Figure 4, a cylinder is indicated by the fererence character 34 in which the piston opcrates, the piston being supplied with the usual piston rod 36 to which the sheave and sheave housing (not shown in Figure 4), are

connected. The piston '35 in this form of the invention is provided with valves 37 operating in one direction, and a substantially small gravity controlled valve 38, the valves 37 being normally seated by means of the coiled springs 39 so that movement of the piston ill be retarded under severe strains.

An opening 40 is provided in the piston and allows the liquid within the cylinder to pass gradually from one side of the piston 35 to the other under strain directed to the sheave and housing connected with the rod 36, by expansion and contraction of the cable operating over the sheave.

Figure 5 illustrates the usual elevator construction wherein a floating sheave such as indicated at 41 is used, the car being indicated at 42 and the counterweight being shown at 43. The cable is indicated by the a reference character 44 and is shown as slack cable slack occurs should the car or counterweight move to a position to rest on the buffers in the elevator pit.

I claim:

1. A compensating elevator sheave support including a base having a passageway, cylinders in communcation with the passageway, said cylinders having longitudinal passageways communicating with the cylinders at their ends, pistons operating in the cylinders, valves for controlling the passage of liquid through the passageways and the pistons, a

housing, a sheave operating in the housing, and piston rods connected with the pistons and connected with the sheave housing to control movement of the housing.

2. A compensating elevator sheave support including a base having a passageway, cylinders mounted on the base and communicating with the passageway, longitudinal passageways on the cylinders and communicating with the cylinders at the ends of the cylinders, pistons operating in the cylinders, one way valves in the pistons for permitting liquid to pass through the pistons when the pistons move to the bottoms of the cylinders, piston rods connected with the pistons, a sheave housing connected with the piston rods, and a sheave operating in the sheave housing.

3. A compensating elevator sheave support including a base having a longitudinal pas sageway, cylinders mounted on the base and connnunicating with the passageway at the ends thereof, longitudinal passageways formed laterally of the cylinders and communicating with the cylinders at the ends of the cylinders, spring pressed valves for controlling the passage of liquid from the cylinders to the passageways, pistons operating in the cylinders and having piston rods,

cylinders mounted on the base and in communication with the passageway, a longi tudinal passageway forming, a part of each cylinder and having valve openings at the upper ends of the longitudinal passageways, valves operatingin the openings, an adjustable spring supporting member disposed ad jacent to the valves, springs contacting with the valves and resting against the spring supporting member for normally urging the valves to their seats, and a piston operating in the cylinder.

5. In an elevator, the combination with a car, hoisting cable and pulley over which the cable operates, of a compensating pulley support including a housing, lateral pistons mounted in the housing, cylinders in which the pistons operate, a passageway establishing communication between the cylinders, said cylinders having lateral passageways extending to the upper ends thereof, and valves in the passageways for controlling the flow of liquid through the passageways, said valves being adapted to regulate the movements of the housing.

6. In an elevator system, a tensioning sheave mechanism for the elevator compensating cables comprising; two spaced pistonand-cylinder devices, each of said devices having a cylinder element and a piston element, one of which elements is movable relatively to the other element; a frame connecting one of said elements of one piston-andcylinder device with the corresponding element of the other piston-and-cylinder device; a tensioning sheave rotatably secured to said frame between said two piston-andcylinder devices; means by which the other of said elements of each piston-and-cylinder device may be secured in the elevator pit; and means for controlling the passage of fluid from one side of each piston element to the other side thereof.

7. In an elevator system, a tensioning sheave mechanism for the elevator compensating cables comprising; a tensioning sheave; a frame in which said tensioning sheave is rotatably mounted; two piston-and-cylinder devices positioned alongside said tensioning sheave, one on eitherside thereof, each of said devices having acylinder element and a piston element, one of which elements is movable and the other of which is stationary, said movable elements being connected to said sheave-supporting frame and said stationary elements being secured in the elevator pit; means for controlling the passage of fluid from one side of each piston to the other side thereof so that sudden upward movement of said tensioning sheave is opposed; and a pressure-equalizing connection between said two piston-and-cylinder devices.

In testimony that I claim the foregoing as my own, I have hereto aflixed my signature;

BLAKE PALM. 

